1. Field of the Invention
This invention relates in general to a shielding device for a source of radiation, and more particularly, device to a modular and portable X-ray collimator and shielding
2. Description of the Prior Art
The relevant field of the present invention is best illustrated by the following references:
______________________________________ Rossem 4,286,169 Applegate 3,737,661 Gates 3,649,426 Moore 3,161,776 Nagey 3,113,089 Shasky 2,794,128 Humphreys 2,137,122 Struck 2,135,019 Kelly 1,156,906 Myers 965,533 French application 1,374,225 French application 1,286,503 German application 1,073,687 ______________________________________
X-rays are short wave electronic magnetic vibrations which can penetrate solid manner. They are produced when, in the vacuum, electrons are released, accelerated and then abruptly retarded. Such rays are detrimental to the living cells and tissues of human beings.
Attempts have been continually made to shield the harmful radiations. The maximum allowed radiation for health protection standards for non-occupational personnel is approximately two milli roentgens/hour. The average critical radiation distance for a conventional X-ray generator during its maximum output is 18.29 meters (60 ft.) from the point of exposure. Contemporary X-ray shielding apparatus are limited in their ability to reduce the radiation field to safe levels within the general proximity of the X-ray source, i.e. within a radius of 3.05 meters (10 ft.) from the source of radiation.
Known prior shielding devices are limited in their ability to eliminate radiation, especially when the object to be X-rayed is large and relatively flat, such as an aircraft structure. Moreover, none of the prior known shielding devices combine the shielding capability with the portability and modular construction provided by the present invention.
The Applegate patent, for instance, describes a shielded adaptor attachable to a portable X-ray device having a collimator and a container rotationally and pivotally mounted thereon. The container has an upper and an overlapping bottom part between which portion of the object to be X-rayed can be completely enclosed.
The French patent No. 1,374,225 teaches the use of a shield in combination with a clenching joint surrounding the object to be X-rayed.
Neither reference discloses a portable, light-weight X-ray device that effectively shields the emitted radiation and can be used to X-ray flat surfaces of large structures.
At present, the primary absorption shielding material used is lead (Pb), which is well characterized by extreme high density and weight. Thus, the present shielding devices are exceedingly heavy, which limits the deportability, assembly, disassembly, storage and transportation of said structures. Such limitations are reflected in the high costs of operation and maintenance of the present shielding devices.
Therefore, there is a long felt need for a portable, lightweight, collimator and scatter shield device which addresses and resolves the above problems.